Question

I think it's A?
Which version of the sentence is most concise?

This paper will be about the fact that water conservation starts at home.

Water conservation at home is as important as major policy changes.

The reasons water conservation is important are actually quite significant.

Water conservation is important due to the fact that it affects us all.

Answer 1

B? I think it'd partially make a concise thesis with that statement.
1st sentence is good too, but it's not addressing the main idea. 3rd sentence is a commentary/opinion.
Last sentence is a commentary.

Answer 2

Ha-ha thank you, this is the one question I couldn't answer.